Aripiprazole, 7-[4-[4-(2,3-dichlorophenyl)-1-piperazinyl]butoxy]-3,4-dihydro-2(1H)-quinolinone, is an antipsychotic drug useful in the treatment of schizophrenia (Merck Index, monograph number 00791, CAS registry number 129722-12-9).
Synthesis and isolation of aripiprazole are described in EP 367141 B1 and U.S. Pat. No. 5,006,528. Additional crystalline anhydrous or hydrous forms are disclosed in WO 03/026659 (conventional hydrate, hydrate A, conventional anhydrate, anhydrate B, anhydrate C, anhydrate D, anhydrate E, anhydrate F, anhydrate G).
Nevertheless, there remains a need for alternative polymorphic forms of aripiprazole which have properties suitable for pharmaceutical processing on a commercial scale. The present invention satisfies these needs by providing novel polymorphic forms of aripiprazole and processes for their production.